学习笔记

在用strtus2的json插件读取数据时，出现了包冲突的问题，搞了老半天才解决， 报错如下： 2010-8-23 17:37:17 org.apache.catalina.core.StandardWrapperValve invoke 严重: Servlet.service() for servlet default threw exception java.lang.NoClassDefFoundError: com/opensymphony/xwork2/util/TextUtils at com.googlecode.jsonplugin.JSONUtil.writeJSONToResponse(JSONUtil.java:197) at com.googlecode.jsonplugin.JSONResult.writeToResponse(JSONResult.java:192) at com.googlecode.jsonplugin.JSONResult.execute(JSONResult.java:182) at com.opensymphony.xwork2.DefaultActionInvocation.executeResult(DefaultActionInvocation.java:361) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:265) at com.opensymphony.xwork2.interceptor.DefaultWorkflowInterceptor.doIntercept(DefaultWorkflowInterceptor.java:163) at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) at com.opensymphony.xwork2.validator.ValidationInterceptor.doIntercept(ValidationInterceptor.java:251) at org.apache.struts2.interceptor.validation.AnnotationValidationInterceptor.doIntercept(AnnotationValidationInterceptor.java:68) at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) at com.opensymphony.xwork2.interceptor.ConversionErrorInterceptor.intercept(ConversionErrorInterceptor.java:122) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:195) at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:195) at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) at com.opensymphony.xwork2.interceptor.StaticParametersInterceptor.intercept(StaticParametersInterceptor.java:148) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) at org.apache.struts2.interceptor.MultiselectInterceptor.intercept(MultiselectInterceptor.java:75) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) at org.apache.struts2.interceptor.CheckboxInterceptor.intercept(CheckboxInterceptor.java:94) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) at org.apache.struts2.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:235) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) at com.opensymphony.xwork2.interceptor.ModelDrivenInterceptor.intercept(ModelDrivenInterceptor.java:89) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) at com.opensymphony.xwork2.interceptor.ScopedModelDrivenInterceptor.intercept(ScopedModelDrivenInterceptor.java:128) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) at org.apache.struts2.interceptor.debugging.DebuggingInterceptor.intercept(DebuggingInterceptor.java:267) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) at com.opensymphony.xwork2.interceptor.ChainingInterceptor.intercept(ChainingInterceptor.java:126) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) at com.opensymphony.xwork2.interceptor.PrepareInterceptor.doIntercept(PrepareInterceptor.java:138) at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) at com.opensymphony.xwork2.interceptor.I18nInterceptor.intercept(I18nInterceptor.java:164) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) at org.apache.struts2.interceptor.ServletConfigInterceptor.intercept(ServletConfigInterceptor.java:164) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) at com.opensymphony.xwork2.interceptor.AliasInterceptor.intercept(AliasInterceptor.java:128) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) at com.opensymphony.xwork2.interceptor.ExceptionMappingInterceptor.intercept(ExceptionMappingInterceptor.java:176) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236) at org.apache.struts2.impl.StrutsActionProxy.execute(StrutsActionProxy.java:52) at org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:488) at org.apache.struts2.dispatcher.ng.ExecuteOperations.executeAction(ExecuteOperations.java:77) at org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.doFilter(StrutsPrepareAndExecuteFilter.java:91) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:286) at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844) at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583) at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447) at java.lang.Thread.run(Thread.java:619)


在struts2 的官方上面说struts2.1.x要配合jsonplugin-0.33.jar使用 struts2.0.x配合jsonplugin-0.32.jar 我用的是struts2.1.8和jsonplugin-0.33.jar 但是还是出现上面那个错误，后来google了一下终于是解决了解决方案： 将jsonplugin-0.33.jar替换成json-lib-2.1.jar、struts2-json-plugin-2.1.8.1.jar、struts2-junit-plugin-2.1.8.1.jar 使用这三个包就不会出现冲突了